Even the Catholic Church in Australia supported the announcement - saying the bishops shared ''the feelings of horror and outrage which all decent people feel when they read the reports of sexual abuse and allegations of cover-up'' - but denying there was a systemic problem in the church.

Nicky Davis, spokeswoman for SNAP (Survivors Network of those Abused by Priests) said victims were ''completely overjoyed''.

''There will be mixed emotions as well, because it brings up that our voice has been suppressed for so long and we've been abandoned, but it's a joyous day,'' Ms Davis said.

She said that as she listened to Prime Minister Julia Gillard, ''between sobs, I didn't hear anything I disagreed with. But it's important to consult victims about the terms of reference so that the commission goes to the core issues, and also look at international best practice.''

She said victims had fought for this for decades, and in the early days had been utterly dismissed.

''It's important to remember them - they suffered terribly - and it's also about the ones who never made it.''

Lawyer Viv Waller, who is acting for dozens of abuse victims in Ballarat, said she was excited and elated.

''It restores the community's confidence and faith in the democratic process and the separation of church and state,'' she said.

''It's a great relief to my clients that, contrary to the way it has behaved over the years, the Church is not above the law.''

Advocate and author Chrissie Foster, two of whose daughters were appallingly abused, said she was blown away. ''Justice has been denied so far. We've been telling our story for 16 years. It goes out there, and nothing happens.''

She said the Victorian parliamentary inquiry was a step in the

right direction, ''but this is what we need''.

Survivor Noreen Wood said: ''The victims have always believed that eventually the gates of hell would open up and swallow abusers. At last, the truth can come out.''

Catherine Arthur, who was abused first as a nine-year-old girl, then as an adult nun, said she was over the moon. ''It's about time. It's too much for just the Victorian inquiry.''

Helen Last, of In Good Faith, a consultant to the Melbourne Victims Collective who gave evidence at the Victorian inquiry on Monday, said victims were delighted that the federal government has listened to their concerns, and looked forward to their day before the commission.

Broken Rites spokesman Bernard Barrett welcomed a national royal commission, ''provided that the focus is on the cover-up''.

''What we want is an inquiry into the concealing of crimes, which the Victorian inquiry was getting round to,'' he said.

The Catholic Church statement from the bishops' conference said child sex abuse was a serious issue not just for the church but the whole community because abuse occurred in families, community groups, schools and other organisations as well.

It admitted there were ''significant problems'' in some dioceses and religious orders, but said ''talk of systemic problems of sexual abuse in the Catholic Church is ill-founded and inconsistent with the facts''.